The following United States patent applications, which were concurrently filed with this one on Oct. 28, 1999, are fully incorporated herein by reference: Method and System for Navigating a Catheter Probe in the Presence of Field-influencing Objects, by Michael Martinelli, Paul Kessman and Brad Jascob; Patient-shielding and Coil System, by Michael Martinelli, Paul Kessman and Brad Jascob; Navigation Information Overlay onto Ultrasound Imagery, by Paul Kessman, Troy Holsing and Jason Trobaugh; Coil Structures and Methods for Generating Magnetic Fields, by Brad Jascob, Paul Kessman and Michael Martinelli; Registration of Human Anatomy Integrated for Electromagnetic Localization, by Mark W. Hunter and Paul Kessman; System for Translation of Electromagnetic and Optical Localization Systems, by Mark W. Hunter and Paul Kessman; and Surgical Sensor, by Mark W. Hunter, Sheri McCoid and Paul Kessman.
A. Field of the Invention
The present invention relates to wireless remote medical devices. The invention has particular application when used with a method and system for determining the position of a wireless catheter probe being used during a surgical procedure.
B. Description of the Related Art
Various locating systems have been used in the past to determine the position of an object such as the tip of an endoscope or a catheter within the human body.
Systems and methods are known for determining the location of a catheter or endoscopic probe inserted into a selected body cavity of a patient undergoing a surgical procedure. For example, there exist systems that may use acoustics, optics, conductance and electromagnetics to locate or xe2x80x9clocalizexe2x80x9d a medical instrument in an anatomical body. In an electromagnetic system, location data may be obtained from electrical measurements of voltage signals that are induced within a sensing coil affixed to the distal end of the catheter prove. A voltage is induced in the sensing coil in response to pre-specified electromagnetic fields that project into the anatomical region of interest which contains all prospective locations of the catheter probe. The electrical measurements of the induced signals may provide sufficient information to compute the angular orientation and the positional coordinates of a coil in a sensor, and hence the catheter probe, which collectively define the location of the coil.
Regardless of the technical particulars of a surgical localization system, each system typically includes a component internal to the patient associated with a medical device and a component external to the patient for calculating the position of the medical instrument.
The present invention is directed to improving communication links between internal and external surgical navigation components and to providing wireless power to internal components.
The invention in its broadest sense may include one or more of the following aspects alone or in combination with one or more elements:
an apparatus and method for locating a wireless sensor/transmitter within an anatomical body,
at least one signal generator for sending reference signals through the anatomical body to be received by the sensor/transmitter and to be wirelessly re-transmitted by the sensor/transmitter as positional signals indicative of a current location of the sensor/transmitter in the anatomical body,
a receiver for receiving positional signals from the wireless sensor/transmitter,
a processor for computing a position of a wireless sensor/transmitter as a function of the positional signals transmitted to a receiver, and a circuit associated with the processor for outputting position image information to a display device,
a wireless sensor/transmitter for use in surgical procedures to track the movement of structures within an anatomical body having a portion for receiving a reference signal from a reference signal generator, and a portion for wirelessly transmitting the reference signal as a positional signal indicative of a current position of the sensor and hence the probe,
a sensor having a coil adapted to have a voltage induced therein by a signal generator separated from the coil by a distance,
a sensor having a circuit for powering the transmitter using an induced voltage.
It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as claimed.
The accompanying drawings, which are incorporated into and constitute a part of this specification, illustrate several embodiments of the invention and together with the description, serve to explain the principles of the invention.